Browsing by Author "Skadiņš, Ingus"
Now showing 1 - 20 of 23
Results Per Page
Sort Options
Item Adhesion and colonisation of microorganisms on porous TiO2 and TiO2-Silver Biomaterials(2019) Skadiņš, Ingus; Mičko, Lana; Zvaigzne, Liene; Narkevica, I.; Kroiča, Juta; Department of Biology and MicrobiologyItem Antibacterial effects of oak bark (Quercus robur) and heather herb (Calluna vulgaris L.) extracts against the causative bacteria of bovine mastitis(2022-09) Šukele, Renāte; Skadiņš, Ingus; Koka, Rudīte; Bandere, Dace; Department of Pharmaceutical Chemistry; Red Cross Medical College of Rīga Stradiņš University; Department of Biology and MicrobiologyBackground and Aim: Bovine mastitis has a negative impact on animals, and improper antibiotic use has caused an increase in bacterial resistance. Therefore, medicinal plants could serve as an alternative treatment for this condition. Polyphenols have potential as antibiotic agents. Oak bark has long been used as a medicine and has shown antibacterial effects. Moreover, research on heather plant demonstrated that it has antibacterial properties. This study aimed to assess the antibacterial effects of oak (Quercus robur) bark and heather (Calluna vulgaris L.) herb extracts against common bovine mastitis pathogens. Materials and Methods: Dried oak bark and heather herb were used to prepare extracts using 30%, 50%, and 70% ethanol and acetone as solvents. Their polyphenol content was determined using the Folin-Ciocalteu method. Bovine mastitis-inducing clinical isolates of Escherichia coli, Streptococcus agalactiae, Streptococcus uberis, Serratia liquefaciens, Staphylococcus aureus, and reference cultures of S. aureus and E. coli were used for antibacterial tests. All extracts were screened through a disk diffusion test to ascertain their antibacterial effects, and the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined for the most effective extracts. Results: Oak bark extracts had variable antibacterial effects against S. aureus and Streptococcus strains, but no statistically significant difference was observed in activity against E. coli. The disk diffusion test showed that the oak bark extracts obtained using acetone and ethanol at 30% yielded the best results. However, the 70% acetone oak extract alone affected all types of bacteria. Further antibacterial tests of 70% acetone and 30% ethanol oak extracts revealed that the lowest MIC and MBC scores were against S. aureus strains and E. coli reference cultures. Conversely, the heather herb extracts exhibited broader activity against all types of bacteria, although better results were observed against Gram-positive bacteria. There was also a negative correlation between solvent concentration and antibacterial effect (p < 0.05, r = −0.507). The highest inhibition zone scores and broadest spectrum were observed in samples prepared in 30% ethanol. There was no statistically significant correlation between the phenolic content of plants and their antibacterial effects. Conclusion: Oak bark and heather extracts could be used as potential antibacterial agents against bovine mastitis pathogens.Item Antibacterial Efficiency of Antibiotic-Impregnated Biomaterials in an In Vitro and In Vivo Study. Summary of the Doctoral Thesis(Rīga Stradiņš University, 2016) Skadiņš, Ingus; Kroiča, Juta; Šalma, IlzeNowaday, biomaterials are used more frequently and are becoming increasingly important as biomaterials are used in all medical fields, and often the use of biomaterials are of life saving importance. Due to the extensive use and applications of biomaterials, and different types of biomaterials associated infections which are a significant medical problem. Depending on the type of infection, it may increase the patient’s risk of mortality, and increase the total cost of treatment due to necessary replacement of biomaterial. To prevent infection of biomaterials, it is necessary to reduce bacterial adhesion and biofilm formation on the biomaterial. This can be achieved with the use of antimicrobial substances. Local antibiotic substances released from the biomaterial is an advantage compared with most systemic antibiotic which are given to the patients before and after implantation surgery. The aim of this work is to exam the antibacterial efficiency of hydroxyapatite biomaterials with antibiotics (gentamicin or ciprofloxacin) and biodegradable polymer against the most common post-operative causative agents – Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus epidermidis (S. epidermidis). This work also compares the antimicrobial properties of composite materials with biodegradable polymers and without biodegradable polymers. Antibacterial properties of biomaterials were investigated against S. epidermidis and P. aeruginosa by using a standardized disc diffusion method in an agar medium, and in the bacterial suspension. The intensity of Inflammatory cytokines (TNF-α a IL-10) and antibacterial peptides (β-defensīna-2) were tested in an in vivo study after a biomaterial sample implantation in the rabbits subcutaneous pocket and wound contamination with S. epidermidis or P. aeruginosa. The results showed that the biomaterials with biodegradable polymer and antibiotic substances have statistically significantly longer antibacterial time than the biomaterials with antibiotic substances without the biodegradable polymer. The method which was used doesn’t influence the antibacterial properties of biomaterials. The porosity level of biomaterials influences on antibacterial time, the biomaterials with lower porosity level have statistically significantly shorter antibacterial time than biomaterials with higher porosity levels. In vivo study results showed that after composite material implantation with antibiotic substances, levels of inflammatory cytokines and antimicrobial peptides doesn’t increase in the surrounding tissues around biomaterials. Increased levels inflammatory cytokines and antibacterial peptides are in the tissue around biomaterials, after an implantation of biomaterials without antibiotic substances.Item Antibacterial Efficiency of Hydroxyapatite Biomaterials with Biodegradable Polylactic Acid and Polycaprolactone Polymers Saturated with Antibiotics(2016-08-01) Kroiča, Juta; Skadiņš, Ingus; Salma, Ilze; Reinis, Aigars; Sokolova, Marina; Rostoka, Dagnija; Berza, Natalija; Department of Biology and MicrobiologyInfections continue to spread in all fields of medicine, and especially in the field of implant biomaterial surgery, and not only during the surgery, but also after surgery. Reducing the adhesion of bacteria could decrease the possibility of biomaterial-associated infections. Bacterial adhesion could be reduced by local antibiotic release from the biomaterial. In this in vitro study, hydroxyapatite biomaterials with antibiotics and biodegradable polymers were tested for their ability to reduce bacteria adhesion and biofilm development. This study examined the antibacterial efficiency of hydroxyapatite biomaterials with antibiotics and biodegradable polymers against Staphylococcus epidermidis and Pseudomonas aeruginosa. The study found that hydroxyapatite biomaterials with antibiotics and biodegradable polymers show longer antibacterial properties than hydroxyapatite biomaterials with antibiotics against both bacterial cultures. Therefore, the results of this study demonstrated that biomaterials that are coated with biodegradable polymers release antibiotics from biomaterial samples for a longer period of time and may be useful for reducing bacterial adhesion on orthopedic implants.Item Antimicrobial and Antibiofilm Properties of Latvian Honey against Causative Agents of Wound Infections(2023-04-26) Skadiņš, Ingus; Labsvārds, Krišs Dāvids; Grava, Andra; Amirian, Jhaleh; Tomsone, Laura Elīna; Ruško, Jānis; Viksna, Arturs; Bandere, Dace; Brangule, Agnese; Department of Biology and Microbiology; Department of Pharmaceutical ChemistryHoney is widely used in traditional medicine and modern wound healing biomaterial research as a broad-spectrum antimicrobial, anti-inflammatory and antioxidant agent. The study’s objectives were to evaluate the antibacterial activity and polyphenolic profiles of 40 monofloral honey samples collected from beekeepers in the territory of Latvia. The antimicrobial and antifungal activity of Latvian honey samples were compared with commercial Manuka honey and the honey analogue sugar solutions–carbohydrate mixture and tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, clinical isolates Extended-Spectrum Beta-Lactamases produced Escherichia coli, Methicillin-resistant Staphylococcus aureus and Candida albicans. Antimicrobial activity was evaluated with the well-diffusion method (80% honey solution w/v) and microdilution method. The honey samples with the highest antimicrobial potential were tested to prevent biofilm development and activity against a preformed biofilm. The principal component analysis of the antimicrobial properties of honey samples vs. polyphenolic profile was performed. Eleven honey samples exhibited antibacterial activity to all investigated bacteria. The antibacterial effect of the samples was most significant on the Gram-positive bacteria compared to the studied Gram-negative bacteria. Latvian honey presents promising potential for use in wound healing biomaterials, opening the possibility of achieving long-term antibacterial effects.Item Antioxidant Status in Patients after Breast Mastopexy and Augmentation(2024-06-26) Jurševičs, Kirils; Jurševičs, Eduards; Krasiļņikova, Jeļena; Šķesters, Andrejs; Lece, Anna; Skadiņš, Ingus; Department of Doctoral Studies; Department of Human Physiology and Biochemistry; Bioķīmijas zinātniskā laboratorija; Department of Biology and MicrobiologyBackground and Objectives: Mammary gland surgery has become very common, but there are complications of these operations, including the concept of breast implant illness (BII) in women with silicone gel breast implants (SBI), who suffer from various symptoms such as myalgia, arthralgia, fatigue, fever, dry eyes, or dry mouth. Silicone biomaterials are synthetic polymers that have their own physical and chemical properties and can exert their effect at the site of use and possibly on the general status of the body, causing inflammation and oxidative stress signs. The aim of the study was to examine components of the blood antioxidant system (AOS) of the mastopexy and breast augmentation patients before the operation, on the first post-op day, and 6 months after surgery. Materials and Methods: Healthy breast surgery patients (women aged 31 to 60 years without visible pathologies) were selected for the study and formed 2 groups: breast lift—mastopexy without silicone biomaterials (I group, 30 patients) and breast augmentation using silicone biomaterials (II group, 28 patients). All patients underwent standard preoperative tests. Glutathione peroxidase (GPxSe) and gamma-glutamyl transferase (GGT) in blood, selenium (Se), selenium protein P (SelPP), and total antioxidant status (TAS) in plasma were measured as AOS parameters. The concentration of vitamin D was also determined. A total of 174 blood tests were performed. Results: Overall, there were no differences in both groups in measured antioxidant system indicators over time; neither changes in objective nor subjective status were observed. However, baseline activity of GPxSe was relatively high but restored to normal values 6 months after surgery. In the mastopexy group, GPxSe decreased from 12,961.7 U/L by 18.9% to 10,513.4 U/L, and in the breast augmentation group, from 15,505.0 U/L by 25.1% to 11,265.5 U/L, which is a decrease of 18.9% and 25.1%, respectively. The patients did not note any complaints; other indicators of standard biochemical tests were within normal limits. Conclusions: The two types of surgical interventions, breast mastopexy and augmentation of the mammary glands, do not significantly impact blood AOS and are physiological in nature.Item Ar antibiotiskām vielām impregnētu kompozītmateriālu antibakteriālā darbība in vitro un in vivo. Promocijas darba kopsavilkums(Rīgas Stradiņa universitāte, 2016) Skadiņš, Ingus; Kroiča, Juta; Šalma, IlzeMūsdienās biomateriālus izmanto bieži, un to aktualitāte kļūst arvien nozīmīgāka, jo biomateriālus izmanto visās medicīnas nozarēs, turklāt nereti to lietošana ir dzīvību glābjoša nepieciešamība. Taču biomateriālu plašais izmantojums, dažādie biomateriālu veidi un pielietojums ir saistīts ar būtisku medicīnisku problēmu – biomateriālu saistītām infekcijām. Atkarībā no infekcijas veida un lokalizācijas var palielināties pacienta letalitātes risks un kopējās ārstnieciskās izmaksas, jo implantātu bieži nākas aizvietot ar jaunu. Lai novērstu biomateriālu infekcijas, ir jāsamazina baktēriju adhēzija un biofilmu veidošanās. To iespējams panākt, biomateriālam pievienojot antibiotiskās vielas. Lokālai antibiotisko vielu izdalei no biomateriāla ir daudz priekšrocību, salīdzinot ar sistēmisko antibiotisko vielu nozīmēšanu pacientiem pirms un pēc implantācijas operācijas. Šī darba mērķis ir noskaidrot kompozītmateriālu ar antibiotiskajām vielām (gentamicīnu vai ciprofloksacīnu) un biodegradējamu polimēru antibakteriālo efektivitāti pret vienu no biežākajiem pēcoperācijas infekciju ierosinātājiem – Pseudomonas aeruginosa (P. aeruginosa) un Staphylococcus epidermidis (S. epidermidis), kā arī salīdzināt antibakteriālās īpašības kompozītmateriāliem ar biodegradējamu polimēru un bez tā. Biomateriālu antibakteriālās īpašības pret S. epidermidis un P. aeruginosa tika pētītas, izmantojot standartizēto disku difūzijas metodi agara barotnē, kā arī baktēriju suspensijā. Iekaisuma citokīnu (TNF-α un IL-10) un antibakteriālo peptīdu (β-defensīna-2) intensitāte audos ap implantēto biomateriālu tika izvērtēta in vivo pētījumā pēc biomateriālu paraugu implantācijas truša zemādas kabatā un kontaminācijas ar S. epidermidis vai P. aeruginosa. Rezultāti atklāja, ka biomateriāliem ar bionoārdāmo polimēru un antibiotiskajām vielām antibakteriālās darbības laiks ir statistiski ticami ilgāks nekā biomateriāliem ar antibiotiskajām vielām bez bionoārdāma polimēra. Antibakteriālās darbības laiku neietekmē metode, ar kādu nosaka biomateriālu antibakteriālās īpašības, bet to būtiski ietekmē biomateriālu porainības līmenis, jo biomateriāliem ar zemāku porainības līmeni ir statistiski ticami īsāks antibakteriālās darbības laiks nekā biomateriāliem ar augstāku porainības līmeni. In vivo pētījuma rezultāti rāda, ka pēc antibiotisko vielu saturošu kompozītmateriālu implantācijas apkārtējos audos ap biomateriālu nenovēro paaugstinātu iekaisuma citokīnu un antibakteriālo peptīdu klātbūtni. Paaugstināta iekaisuma citokīnu un antibakteriālo peptīdu ekspresija tiek novērota audos ap biomateriālu pēc antibiotikas nesaturošu biomateriālu implantācijas un kontaminācijas ar baktēriju tīrkultūru.Item Ar antibiotiskām vielām impregnētu kompozītmateriālu antibakteriālā darbība in vitro un in vivo. Promocijas darbs(Rīgas Stradiņa universitāte, 2016) Skadiņš, Ingus; Kroiča, Juta; Šalma, IlzeMūsdienās biomateriālus izmanto bieži, un to aktualitāte kļūst arvien nozīmīgāka, jo biomateriālus izmanto visās medicīnas nozarēs, turklāt nereti to lietošana ir dzīvību glābjoša nepieciešamība. Taču biomateriālu plašais izmantojums, dažādie biomateriālu veidi un pielietojums ir saistīts ar būtisku medicīnisku problēmu – biomateriālu saistītām infekcijām. Atkarībā no infekcijas veida un lokalizācijas var palielināties pacienta letalitātes risks un kopējās ārstnieciskās izmaksas, jo implantātu bieži nākas aizvietot ar jaunu. Lai novērstu biomateriālu infekcijas, ir jāsamazina baktēriju adhēzija un biofilmu veidošanās. To iespējams panākt, biomateriālam pievienojot antibiotiskās vielas. Lokālai antibiotisko vielu izdalei no biomateriāla ir daudz priekšrocību, salīdzinot ar sistēmisko antibiotisko vielu nozīmēšanu pacientiem pirms un pēc implantācijas operācijas. Šī darba mērķis ir noskaidrot kompozītmateriālu ar antibiotiskajām vielām (gentamicīnu vai ciprofloksacīnu) un biodegradējamu polimēru antibakteriālo efektivitāti pret vienu no biežākajiem pēcoperācijas infekciju ierosinātājiem – Pseudomonas aeruginosa (P. aeruginosa) un Staphylococcus epidermidis (S. epidermidis), kā arī salīdzināt antibakteriālās īpašības kompozītmateriāliem ar biodegradējamu polimēru un bez tā. Biomateriālu antibakteriālās īpašības pret S. epidermidis un P. aeruginosa tika pētītas, izmantojot standartizēto disku difūzijas metodi agara barotnē, kā arī baktēriju suspensijā. Iekaisuma citokīnu (TNF-α un IL-10) un antibakteriālo peptīdu (β-defensīna-2) intensitāte audos ap implantēto biomateriālu tika izvērtēta in vivo pētījumā pēc biomateriālu paraugu implantācijas truša zemādas kabatā un kontaminācijas ar S. epidermidis vai P. aeruginosa. Rezultāti atklāja, ka biomateriāliem ar bionoārdāmo polimēru un antibiotiskajām vielām antibakteriālās darbības laiks ir statistiski ticami ilgāks nekā biomateriāliem ar antibiotiskajām vielām bez bionoārdāma polimēra. Antibakteriālās darbības laiku neietekmē metode, ar kādu nosaka biomateriālu antibakteriālās īpašības, bet to būtiski ietekmē biomateriālu porainības līmenis, jo biomateriāliem ar zemāku porainības līmeni ir statistiski ticami īsāks antibakteriālās darbības laiks nekā biomateriāliem ar augstāku porainības līmeni. In vivo pētījuma rezultāti rāda, ka pēc antibiotisko vielu saturošu kompozītmateriālu implantācijas apkārtējos audos ap biomateriālu nenovēro paaugstinātu iekaisuma citokīnu un antibakteriālo peptīdu klātbūtni. Paaugstināta iekaisuma citokīnu un antibakteriālo peptīdu ekspresija tiek novērota audos ap biomateriālu pēc antibiotikas nesaturošu biomateriālu implantācijas un kontaminācijas ar baktēriju tīrkultūru.Item Can Our Blood Help Ensure Antimicrobial and Anti-Inflammatory Properties in Oral and Maxillofacial Surgery?(2023-01) Mičko, Lana; Šalma, Ilze; Skadiņš, Ingus; Egle, Karina; Šalms, Ģirts; Dubnika, Arita; Department of Oral and Maxillofacial Surgery and Oral Medicine; Department of Biology and MicrobiologyIn recent decades, the potential of PRF has been extensively studied. The number of studies about PRF has increased three times since the year 2012, but the full spectrum of its fundamental properties, such as antimicrobial and anti-inflammatory activity, is not clearly described. In oral and maxillofacial surgery, PRF is described in alveolar ridge preservation, orthognathic surgery, cleft lip and palate surgery, maxillary sinus augmentation, and dental implant placement as demonstrating favorable results and its clinical advantages. The structural complexity, inhomogeneous nature, and clotting ability of PRF make its antimicrobial effect evaluation complicated. Nevertheless, most of the used antimicrobial testing methods are based on antibacterial agent diffusion ability in culture media. Because the oral and maxillofacial region is the most frequent area of PRF application, its antimicrobial activity evaluation also prevails in the oral microbiome. PRF’s biological potential is highly dependent on the specific preparation protocol and methodology used; it should be carefully prepared and kept under proper conditions to keep cellular content alive. PRF’s influence on living cells demonstrates a stimulating effect on bone regeneration, and an angiogenetic effect, and it provides anti-inflammatory activity. According to analyzed studies, PRF demonstrated success in oral and maxillofacial surgery in various methods of application. Antibacterial and anti-inflammatory properties were proven by antibacterial activity against different bacterial species, sustained growth factor, sustained release, and cell activity on the material application. Accurately and correctly prepared PRF can ensure antibacterial and anti-inflammatory properties, and it can be a beneficial clinical tool in oral and maxillofacial surgery.Item Case report : Jejunal diverticulosis with chronic interstitial and mesenteric adhesions, chronic mesenteric volvulus, and decompensated small-bowel obstruction(2024-04) Vanka, Šarlote Agate; Rudzitis, Janis; Skadiņš, Ingus; Kroiča, Juta; Miļuna-Meldere, Sintija; Dreijers, Janis; Faculty of Medicine; Department of Biology and MicrobiologyIntroduction: Jejunal diverticulosis has not gained significant attention because of its rarity and typically asymptomatic course as well as the relative diagnostic inaccessibility of the jejunum. This report presents a rare case of jejunal diverticulosis complicated with chronic interstitial and mesenteric adhesions, chronic mesenteric volvulus, and decompensated small-bowel obstruction. Presentation of case: An 84-year-old man was admitted to the emergency room with a 24-h history of acute colicky abdominal pain. He denied other signs or symptoms. The preoperative diagnosis based on physical and radiologic evaluations was challenging, and only diagnostic laparoscopy revealed extensive small-bowel diverticulosis. Midline laparotomy was performed as definitive surgery, revealing diverticulosis in the proximal 2-m section of the jejunum, starting approximately 20 cm from Treitz's ligament; the affected section was resected. The postoperative recovery was excellent. The histopathologic report confirmed substantial jejunal diverticulosis with chronic fibrosis, adhesions, and strictures. Discussion: Histopathologic evaluation is necessary because tumors can be misdiagnosed as diverticula. This case report should serve as a reminder for surgeons to be cognizant of the signs of uncommon conditions, such as jejunal diverticulosis. Conclusion: Albeit rare, jejunal diverticulosis should be considered in the differential diagnosis of acute abdomen.Item The Correlation of Swedish Snus, Nicotine Pouches and Other Tobacco Products with Oral Mucosal Health and Salivary Biomarkers(2022-08) Miļuna, Sintija; Melderis, Ričards; Briuka, Loreta; Skadiņš, Ingus; Broks, Renārs; Kroiča, Juta; Rostoka, Dagnija; Department of Prosthetic Dentistry; Department of Biology and MicrobiologyIn society, tobacco products, such as e-cigarettes, and smokeless tobacco products, such as snus and nicotine pouches, are becoming more attractive. There is still a lack of information regarding the effects of these products on the oral mucosa and oral saliva biomarkers. The aim of this study is to evaluate oral mucosa and the presence of inflammatory biomarkers IL-6, IL-1, IL-8, TNF alpha and LRG-1 in saliva. Respondents were divided in four groups based on their tobacco product usage. Oral examination was carried out, saliva samples were taken, and the detection of IL-6, IL-8, IL-1, TNF alpha and LRG-1 levels in saliva was carried out. Out of the tobacco users, 30.8% were snus users, 48.7% were cigarette users and 20.5% were e-cigarette users. The control group was composed of respondents who did not use any tobacco products. E-cigarettes were used more by women, but snus was used more by men. Mucosal changes were seen in the group of snus users, and mucosal changes were only seen in men who had used 5–10 tobacco units per day for 5–10 years. Increased IL-6 levels in saliva were detected in respondents who also experienced mucosal changes. Mucosal changes were white, leathery and localized at the site where snus sachets were placed. Saliva, as an easily available biofluid, could be used as a first tool to detect potentially precancerous signs, but the LRG1 marker cannot be used as a prognostic marker.Item The Effects of Nicotine Pouches and E-Cigarettes on Oral Microbes : A Pilot Study(2024-07-24) Miļuna-Meldere, Sintija; Rostoka, Dagnija; Broks, Renārs; Vīksne, Kristīne; Ciematnieks, Rolands; Skadiņš, Ingus; Kroiča, Juta; Department of Prosthetic Dentistry; Department of Biology and Microbiology; Institute of Oncology and Molecular GeneticsIt remains uncertain whether nicotine pouches and electronic cigarettes alter the oral environment and result in a high presence of periodontopathogenic bacteria in saliva, compared to that among cigarette users or non-tobacco users. In this study, saliva samples were collected from respondents using nicotine pouches, electronic cigarettes, and conventional cigarettes, alongside a control group of non-tobacco users. Polymerase chain reaction was used to identify clinical isolates of the following periodontal bacteria: Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Fusobacterium nucleatum, Fusobacterium periodonticum, Porphyromonas endodontalis, and Rothia mucilaginosa. The presence of some periodontal pathogens was detected in the saliva samples from users of nicotine pouches, electronic cigarettes, and conventional cigarettes but not in samples taken from the control group. Therefore, the initial results of this pilot study suggest that the presence of periodontopathogenic bacteria in the saliva of nicotine pouch and electronic cigarette users could alter the oral microbiome, leading to periodontal diseases. However, further quantitative investigation is needed. Keywords: pathogenic miItem EFFICACY OF FACIAL MASK USE IN COVID-19 TRANSMISSION USING A BACTERIAL MODEL(2024-03-04) Tomiņa, Katrǐna; Kroiča, Juta; Dovbenko, Anastasija; Skadiņš, Ingus; Department of Biology and MicrobiologyThe prevention of COVID-19, caused by SARS-CoV-2, involves reducing transmission of infectious respiratory droplets and aerosols with different methods, including the use of face masks. There have been a variety of studies published about the effectiveness of face masks - they have been recognised as an inexpensive yet expedient prevention method. In this research we aimed to investigate the microbial contamination of used face masks and to compare the results based on mask usage time to determine the efficiency of facial mask use against COVID-19. Microbiological contamination of 51 used face masks was analysed by the imprinting method on suitable cultivation agars and colony forming units were determined. The majority of microorganisms found in our study were those of normal human skin and respiratory tract microbiota. A greater number of bacterial species was found on the outsides of the facial masks, which furthermore increased with prolonged usage time. We conclude that face mask use is effective in both detaining excreted microorganisms as well as protecting the wearer from microbes in the air, and therefore, should be implemented in the prevention strategies of respiratory diseases. Furthermore, our results show the importance of correct facial mask usage by their contamination with a spectrum of microorganisms.Item Failure or future? Exploring alternative antibacterials : a comparative analysis of antibiotics and naturally derived biopolymers(2025-02-03) Sceglovs, Artemijs; Skadiņš, Ingus; Chitto, Marco; Kroiča, Juta; Salma-Ancane, Kristīne; Department of Biology and MicrobiologyThe global crisis of antimicrobial resistance (AMR) is escalating due to the misuse and overuse of antibiotics, the slow development of new therapies, and the rise of multidrug-resistant (MDR) infections. Traditional antibiotic treatments face limitations, including the development of resistance, disruption of the microbiota, adverse side effects, and environmental impact, emphasizing the urgent need for innovative alternative antibacterial strategies. This review critically examines naturally derived biopolymers with intrinsic (essential feature) antibacterial properties as a sustainable, next-generation alternative to traditional antibiotics. These biopolymers may address bacterial resistance uniquely by disrupting bacterial membranes rather than cellular functions, potentially reducing microbiota interference. Through a comparative analysis of the mechanisms and applications of antibiotics and antibacterial naturally derived biopolymers, this review highlights the potential of such biopolymers to address AMR while supporting human and environmental health.Item Histopathological Findings of Oral Mucosa in Smokeless Tobacco Users : Case Report(2022-12-30) Miļuna, Sintija; Melderis, Ričards; Sperga, Māris; Skadiņš, Ingus; Kroiča, Juta; Rostoka, Dagnija; Department of Biology and Microbiology; Department of PathologyBackground: New tobacco products, such as smokeless tobacco, are becoming more popular every year. In talking with our patients, we determined several reasons for that trend. The sale of these products is prohibited in many countries; hence, people obtain the product illegally. This is important, since when these products are stored under inappropriate conditions and temperatures, the quality and properties of the product change, including their carcinogenic properties. Sometimes people use a lot of this product or more than one tobacco product daily. It is challenging for dental practitioners to question their patients about tobacco consumption and more challenging to visually detect oral mucosal changes, because patients usually do not have concerns or they do not pay attention. Methods: In the two cases presented here, the patients did not have any pain, nor did they notice when the lesions appeared. These patients used conventional cigarettes for some time and then switched to smokeless tobacco due to relocation to Latvia. Soft tissue excision was performed and sent for histopathological examination. Results: The findings were proliferation of oral epithelial cells from buccal region, their overgrowth, an excessive amount of fibroblasts, cell destruction and necrosis, and a large amount of inflammatory cells, eosinophil leukocytes, and plasma cells. Conclusion: We can conclude that these intraoral findings are important risk factors for possibly developing precancerous lesions. Such mucosal changes can occur with different forms of tobacco, including Swedish snus and betel leaves. Dental practitioners should always question patients about tobacco use and regularly check for mucosal changes for early detection.Item The Impact of IL1B rs1143634 and DEFB1 rs11362 Variants on Periodontitis Risk in Phenylketonuria and Type 1 Diabetes Mellitus Patients in a Latvian Population(2024) Emulina, Darta Elizabete; Ābola, Iveta; Brinkmane, Anda; Isakovs, Aleksejs; Skadiņš, Ingus; Moisejevs, Georgijs; Gailīte, Linda; Auzenbaha, Madara; Scientific Laboratory of Molecular Genetics; Department of Conservative Dentistry and Oral Health; Department of Biology and MicrobiologyObjectives: Periodontitis is a multifactorial disease that affects approximately 11% of the global population. The objective of this study was to examine whether, among individuals with phenylketonuria and type 1 diabetes mellitus, those with the IL1B rs1143634 and/or DEFB1 rs11362 genetic variants exhibit a higher periodontitis risk compared to healthy controls. Materials and Methods: In all, 43 phenylketonuria patients (aged 12–53), 28 type 1 diabetes mellitus patients (aged 11–40), and 63 healthy controls (aged 12–53) were included. The evaluation of periodontitis risk was conducted using the Silness–Löe plaque index, the Greene–Vermillion index, and an assessment for the necessity of calculus removal. Genetic variants rs1143634 and rs11362 were genotyped from salivary samples using restriction length polymorphism analysis. Results: The DEFB1 rs11362 variant was associated with higher Silness–Löe and Greene–Vermillion index scores in phenylketonuria patients (p = 0.011 and p = 0.043, respectively). The IL1B rs1143634 variant was associated with lower calculus removal necessity in type 1 diabetes mellitus patients (p = 0.030). Clinical examination showed the worst oral hygiene index scores for PKU patients. PKU patients also reported the least consistent tooth brushing and flossing habits. Conclusions: Genetic associations between DEFB1 rs11362 and IL1B rs1143634 variants and oral hygiene indices were observed in the PKU and T1DM groups, suggesting that genetic factors may contribute to periodontal health differences in these populations. Further research with a larger sample size is needed to confirm these findings and develop targeted oral health interventions.Item Influence of antibiotic-impregnated biomaterials on inflammatory cytokines(2019) Skadiņš, Ingus; Kroiča, Juta; Šalma, Ilze; Reinis, Aigars; Sokolova, Marina; Rostoka, Dagnija; Department of Biology and Microbiology; Department of Oral and Maxillofacial Surgery and Oral MedicineItem Injectable mineralized Sr-hydroxyapatite nanoparticles-loaded ɛ-polylysine-hyaluronic acid composite hydrogels for bone regeneration(2024-11) Rubina, A.; Sceglovs, Artemijs; Ramata-Stunda, Anna; Pugajeva, Iveta; Skadiņš, Ingus; Boyd, A. R.; Tumilovica, A.; Stīpniece, Līga; Salma-Ancane, K.; Department of Biology and MicrobiologyIn this study, multifunctional injectable mineralized antibacterial nanocomposite hydrogels were prepared by a homogenous distribution of high content of (up to 60 wt%) Sr-substituted hydroxyapatite (Sr-HAp) nanoparticles into covalently cross-linked ɛ-polylysine (ɛ-PL) and hyaluronic acid (HA) hydrogel network. The developed bone-targeted nanocomposite hydrogels were to synergistically combine the functional properties of bioactive Sr-HAp nanoparticles and antibacterial ɛ-PL-HA hydrogels for bone tissue regeneration. Viscoelasticity, injectability, structural parameters, degradation, antibacterial activity, and in vitro biocompatibility of the fabricated nanocomposite hydrogels were characterized. Physical performances of the ɛ-PL-HA hydrogels can be tailored by altering the mass ratio of Sr-HAp. The nanocomposite hydrogels revealed good stability against enzymatic degradation, which increased from 5 to 19 weeks with increasing the mass ratio of Sr-HAp from 40 % to 60 %. The loading of the Sr-HAp at relatively high mass ratios did not suppress the fast-acting and long-term antibacterial activity of the ɛ-PL-HA hydrogels against S. aureus and E. coli. The cell studies confirmed the cytocompatibility and pre-collagen I synthesis-promoting activity of the fabricated nanocomposite hydrogels.Item Injectable Platelet-Rich Fibrin as a Drug Carrier Increases the Antibacterial Susceptibility of Antibiotic—Clindamycin Phosphate(2022-07-03) Egle, Karina; Skadiņš, Ingus; Grava, Andra; Mičko, Lana; Dubniks, Viktors; Šalma, Ilze; Dubnika, Arita; Department of Biology and Microbiology; Department of Oral and Maxillofacial Surgery and Oral MedicineThe aim of this study was to investigate the change in clindamycin phosphate antibacterial properties against Gram-positive bacteria using the platelet-rich fibrin as a carrier matrix, and evaluate the changes in the antibiotic within the matrix. The antibacterial properties of CLP and its combination with PRF were tested in a microdilution test against reference cultures and clinical isolates of Staphylococcus aureus (S. aureus) or Staphylococcus epidermidis (S. epidermidis). Fouriertransform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analysis was done to evaluate the changes in the PRF_CLP matrix. Release kinetics of CLP was defined with ultra-performance liquid chromatography (UPLC). According to FTIR data, the use of PRF as a carrier for CLP ensured the structural changes in the CLP toward a more active form of clindamycin. A significant decrease in minimal bactericidal concentration values (from 1000 µg/mL to 62 µg/mL) against reference cultures and clinical isolates of S. aureus and S. epidermidis was observed for the CLP and PRF samples if compared to pure CLP solution. In vitro cell viability tests showed that PRF and PRF with CLP have higher cell viability than 70% after 24 h and 48 h time points. This article indicates that CLP in combination with PRF showed higher antibacterial activity against S. aureus and S. epidermidis compared to pure CLP solution. This modified PRF could be used as a novel method to increase drug delivery and efficacy, and to reduce the risk of postoperative infection.Item Oral health care knowledge among Phenylketonuria patients in the Latvian population(2024-12) Ābola, Iveta; Intlere, Nikola Anna; Brinkmane, Anda; Laktina, Sabine; Zariņa, Agnese; Vasilevska, Lauma; Skadiņš, Ingus; Moisejevs, Georgijs; Gailīte, Linda; Auzenbaha, Madara; Department of Conservative Dentistry and Oral Health; Scientific Laboratory of Molecular Genetics; Department of Biology and MicrobiologyBACKGROUND: Phenylketonuria (PKU) is an autosomal recessive inherited disorder of phenylalanine (Phe) metabolism that results from a deficiency of phenylalanine hydroxylase (PAH). Patients with PKU rely on amino acid mixtures and low-protein diets, which often exhibit an acidic nature and pose various challenges to oral health. The objective of the study was to evaluate oral care habits of PKU patients in Latvia and the impact of the recommendations developed on improving oral care. MATERIALS AND METHODS: In this study, during a one-month interval before and after the implementation of oral hygiene recommendations, questionnaires were distributed to all patients with PKU diagnosed in Latvia, with a response rate of 78 % (79 of 101). RESULTS: The group older and 18 years of age showed a poorer understanding of oral care even after receiving recommendations, 82 % brushing their teeth twice a day (92 % in the group <18 years of age), continuing 57 % rinsing their mouth after using amino acid formula (75 % in the younger group). Significant improvements were observed only in the respondent group younger than 18 years of age - including increases in toothbrushing twice a day by 25 % ( p = 0.001), dental flossing by 23 % ( p = 0.001), mouth rinsing after amino acid-based formula by 13 % ( p = 0.020). CONCLUSION: This study concludes that PKU patients older and 18 years of age have a poor understanding of maintaining oral hygiene and the use of the necessary supplements to improve it. Activities are needed in the future that would regularly remind and motivate PKU patients to take care of their oral health.